Despite efforts to diagnose and treat HIV infection before patients develop advanced disease, opportunistic infections (OIs) continue to occur in the era of effective antiretroviral therapy (ART), particularly in those who have not yet been diagnosed with HIV and in those who are not receiving therapy. In the US, approximately 1/3 of patients have a CD4 cell count below 200/mm3 at the time of HIV diagnosis, placing them at risk for OIs.1

Although most OIs occur in patients with CD4 cell counts below 200/mm3, a small residual risk remains even in those with higher counts. A recent analysis of patients with CD4 cell counts >200/mm3 found that esophageal candidiasis, Kaposi Sarcoma and pulmonary tuberculosis were the most common opportunistic conditions in this population. 2 Factors associated with increased risk of AIDS-defining illness (ADI) in patients with a CD4 cell count >500/mm3 included injection drug use, older age and having a HIV RNA >10,000 copies/mL.2 The incidence of OIs appears to level off at a CD4 cell count of 750/mm3, suggesting immune reconstitution is near complete at this level.2